Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Lie on your side with a dumbbell, palm facing down. Rotate your forearm upwards (supination) to lift the weight, maintaining a 90-degree bend in your elbow and a stable forearm. Slowly reverse the motion to return to the starting position, then switch sides.
Focus on controlled movements to maximize muscle activation. Keep your elbow bent at 90 degrees and your forearm stable against your side. Adding a cushion under your forearm can increase the intensity. Try seated variations or adjust your arm position for different feels. Slightly offset your grip on the dumbbell to increase the resistance.
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